Overdose

When we look back on the health-care plans of the 2008 campaign, we may wonder that no one chose to face up to one of the most troubling recent developments in American medicine. Yes, various presidential hopefuls have put forth plans containing detailed provisions to cover the uninsured, bring down costs, and improve the astonishingly uneven quality of health care. But no candidate has discussed the most dramatic change now under way in our medical system, a change that may negate many of the benefits of the plans on offer: the flood of new doctors coming down the pipeline.

Over the next eight years, medical schools are aiming to boost enrollment by as much as 30 percent above 2002 levels. More than a dozen new medical schools are being built or considered, and many of the nation’s 125 existing schools are planning to expand—increasing the number of doctors minted each year from 16,000 to nearly 21,000. This expansion represents a stunning policy reversal by the Association of American Medical Colleges and the Council on Graduate Medical Education, which advises the federal government on how many residency positions to fund. Over the past 15 years, both organizations have raised concerns about the number of medical-school graduates, in the belief that having trained too many doctors in the 1970s and ’80s, we would see a glut of physicians. Now the AAMC is warning that we’ll be at least 100,000 doctors short by 2025 unless we hurry up and train more.

Behind the change of heart lies a cadre of economists and physicians who argue that demographic changes will make doctors scarce. First and foremost, they say, the population is expanding and the Baby Boomers are aging, resulting in more people to care for—especially more old and sick people. Doctors are aging too, and many are retiring. Add to that a decline in the number of hours physicians are willing to put in each day and a few incipient signs of a shortage (notably longer waiting times for appointments and rising salaries for young doctors), and the conclusion that we should expand the physician workforce seems like a no-brainer.

And it would be, if not for all the complications. Those incipient signs, many experts note, may suggest something other than a shortage, and the projections for the number of doctors we’ll need aren’t all that clear-cut. Some experts would even go so far as to suggest we need fewer doctors, not more. Elliott Fisher, a physician and researcher at the Center for Evaluative Clinical Sciences at Dartmouth Medical School, quipped at a recent gathering at the Institute of Medicine, “If we sent 30 percent of the doctors in this country to Africa, we might raise the level of health on both continents.”

The physician workforce estimates rest on two critical assumptions, both of which are probably wrong.

The first is that the number of doctors practicing today is about right and that the market would send signals if supply were exceeding demand. This seems sensible enough, at least on the face of it. For most goods and services, after all, supply in any given community is limited by demand, a measure both of how much consumers need or want the product and of how able they are to pay for it. The number of car dealers in your town, for instance, depends on the number of people who want cars and can afford them.

The ability of patients to pay does help determine the number of doctors in any given community; physicians tend to congregate in places where incomes are higher and patients are more likely to be insured. (And to be sure, physicians are in short supply in parts of the country where relatively few people have health insurance, especially rural areas.) But the other component of demand—how much health care patients want or need—has far less influence over the supply of physicians. That’s because for the most part it’s your doctor and not you, the consumer, who determines how much care you receive. When your doctor says you need a CT scan, you get one. When your doctor says you should go to the hospital, you go. Doctors, in effect, generate some of the demand for their services, so that even when there are large numbers of them per capita, they can keep their appointment books full. There is a growing consensus among health-care analysts that this perverse feature of medical economics is spurring a great deal of unnecessary care. And there’s a corollary: New physicians won’t necessarily go to (poor, rural) places that may need doctors. Many will go to affluent areas and places featuring a high “quality of life”—in other words, places already awash in physicians—where they’ll generate even more demand.